Back in 2014, I sat and observed this in early summer in a classroom environment. Muslim members of the class were getting up around 4AM, guzzling down as much water as possible, eating a fair amount of food, and smoking as much as possible until the sun rose (roughly 5:15 AM).
In the class, by 11 AM, they were stressed out....starting to get dehydrated, and missing their cigarette breaks.
By 1 PM, when the class ended....they were in bad shape. The problem is...they still had another eight-plus hours to go.
In a business environment, I can’t see hiring them because of the dehydration issues. The stress caused by lack of smoking by mid-afternoon is another issue.
Sort of defeats whatever purpose it’s supposed to have, I imagine. That’s the problem with forced religious practices: lack of sincerity. A true God wouldn’t accept it.
Our problem is that some Muslims observe and some don’t. So Mohammed is fasting while Achmed is chowing down on a bacon cheeseburger. It creates a tiny amount of friction because observant Muslims are supposed to be fasting from passing judgment on other Muslims.